1. Technical Field
Embodiments of the present disclosure generally relate to semiconductor integrated circuits and, more particularly, to internal voltage generation circuits.
2. Related Art
In general, semiconductor devices receive a power supply voltage VDD and a ground voltage VSS from an external system to generate internal voltages used in operations of internal circuits thereof. The internal voltages for operating the internal circuits of the semiconductor devices may include a core voltage VCORE supplied to core regions, a high voltage VPP used to drive or overdrive word lines, and a low voltage VBB applied to a bulk region (or a substrate) of NMOS transistors in the core region.
The core voltage VCORE may be a positive voltage which is lower than the power supply voltage VDD supplied from the external system. Thus, the core voltage VCORE may be generated by lowering the power supply voltage VDD to a certain level. In contrast, the high voltage VPP may be higher than the power supply voltage VDD, and the low voltage VBB may be a negative voltage which is lower than the ground voltage VSS. Thus, charge pump circuits may be required to generate the high voltage VPP and the low voltage VBB.
The semiconductor devices, for example, dynamic random access memory (DRAM) devices may be designed to operate at a high speed with low power consumption and large cell capacitance. Thus, most semiconductor devices may be designed to have a deep power-down mode that minimizes a driving current when a data input/output (I/O) operation is not executed. If the semiconductor devices enter the deep power-down mode, internal voltage generation circuits for generating the internal voltages may be turned off to stop generation of the internal voltages.
However, if the deep power-down mode of the semiconductor device terminates, all the internal voltage generation circuits may be turned on to abruptly increase the driving current of the semiconductor device. As a result, a level of the power supply voltage VDD may be suddenly lowered. That is, the power consumption of the semiconductor device may be abruptly increased. In such a case, another semiconductor device sharing the power supply voltage VDD with the semiconductor device may malfunction due to the lowered power supply voltage VDD.